Authors:

Cell structure is controlled to a large degree by the
cytoskeleton, which is
an intracellular polymer network. This cytoskeleton is critical
as it
strongly influences many cellular functions such as motility,
organelle
transport, mechanotransduction and mitosis. In our studies, we
controlled
the thermal environment of living cells and after applying an
increase in
temperature of only 5 $^{o}$C, we observed a change in the
polymer network
as the actin filaments depolymerized. Interestingly, when we then
lowered
the temperature, the actin repolymerized indicating a reversible
phase that
is controlled by the thermal environment. We characterized the
presence of
F-actin and G-actin for these phases through analyzing the
intensity from
immunofluorescent studies for these proteins. The F-actin
concentration
decreased when increasing the temperature from the initial state
and then
increased when decreasing the temperature. Although the cell is
known to be
affected by heat shock responses, this is not a function of just the
polymers as they do not exhibit these polymerization
characteristics when we
probed them as single filaments in vitro. These studies suggest
that the
cell has distinct phases or patterns while maintaining a reversible
equilibrium due to the thermal environment for these networked
polymers.

To cite this abstract, use the following reference: http://meetings.aps.org/link/BAPS.2006.MAR.U26.3